The use of autonomous and semiautonomous unmanned autonomous vehicles (UAVs), also referred to as “drones,” is becoming more common. The range of a UAV may be limited by its stored power supply. Recharging stations may extend the range of a UAV, and with proper placement of recharging stations, the range of a UAV may be effectively unlimited.
Wireless charging stations are well suited for this task, because the UAV does not need to be perfectly aligned with the wireless charging station in order to charge the power supply. Further, the charging station typically does not have exposed conductors that may become dirty or corroded by the elements.
However, reasonably good alignment between charging station and the receive coil on the drone (e.g., within a few centimeters to tens of centimeters) is required for the UAV to be able to utilize wireless power. While Global Positioning System (GPS), inertial navigation, radio navigation, and other fairly standard systems may enable a UAV to move within a few meters of a recharging station, these navigation systems are not sufficiently accurate to obtain the centimeter-level accuracy required to properly dock with a wireless charging station. While more accurate navigation systems exist, such as Differential Global Positioning System equipment, these systems are expensive, relatively heavy, and require increased calibration to achieve the improved location accuracy.